Audio devices are known generally and include hearing aids, earphones and ear pods, among other devices. Some audio devices are configured to provide an acoustic seal (i.e., a “closed fit”) with the user's ear. The seal may cause a sense of pressure build-up in the user's ear, known as occlusion, a blocking of externally produced sounds that the user may wish to hear, and a distorted perception of the user's own voice among other negative effects. However, closed-fit devices have desirable effects including higher output at low frequencies and the blocking of unwanted sound from the ambient environment.
Other audio devices provide a vented coupling (i.e., “open fit”) with the user's ear. Such a vent allows ambient sound to pass into the user's ear. Open-fit devices tend to reduce the negative effects of occlusion but in some circumstances may not provide optimized frequency performance and sound quality. One such open-fit hearing device is a receiver-in-canal (RIC) device fitted with an open-fit ear dome. RIC devices typically supplement environmental sound with amplified sound in a specific range of frequencies to compensate for hearing loss and aid in communication. The inventors have recognized a need for hearing devices that can provide the benefits of both open fit and closed fit.
Elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale or to include all features, options or attachments. For example, the dimensions and/or relative positioning of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of various embodiments of the present invention. Also, common but well-understood elements that are useful or necessary in a commercially feasible embodiment are often not depicted in order to facilitate a less obstructed view of these various embodiments of the present invention. The terms and expressions used herein have the ordinary technical meaning as is accorded to such terms and expressions by persons skilled in the technical field as set forth above except where different specific meanings have otherwise been set forth herein.